Currently in the market, most of music earphones used with music players (e.g., MP3, iPod, iPhone, iPad, Smart Phone, computers or the like) are of the general type that is plugged into the users' ears, and are adapted to satisfy the general demands for music playing and listening. Because the general type of earplugs cannot match auricles of different individuals both in form and in size, leakage of the sound pressure will occur to cause a poor music effect if the earplugs cannot be plugged tightly. On the other hand, if the earphone is plugged into the auricle with a great force to reduce the sound pressure leakage, then uncomfortable feelings such as pains and fullness will be caused.
A fraction of earphones currently available in the market are customized so that the earphones can match the users' auricles in form and in size to improve the tightness and, therefore, to directly improve the music effect. Meanwhile, the receivers in the earphones can be put further into the ear canal to be closer to the ear drum so that the music effect of the earphones can get further improved. The customized earphones are mostly targeted to music fans who lay emphasis on the music effect. The customized earphones are made on a personalized basis through a process of firstly extracting an ear print of the earphone user, fabricating an earphone shell according to the ear print, then putting the receiver into the shell and connecting the receiver with a conductor, and finally putting on a cover to seal the earphone. Manufacturers including Ultimate Ear, Westone, Logitech all produce such customized earphones. However, such customized earphones still have problem of being unable to satisfy the market demands in the following respects:
a) Because the shell thereof makes close contact with the ear canal, a feeling of fullness tends to be caused to affect the music quality;
b) Also because the shell makes close contact with the ear canal in an airtight manner, anaphylaxis of the ear canal tends to occur after a long time of use;
c) Because the shell is too large to extend into the second curve of the ear canal, the long distance from the receiver to the ear drum increases the gain loss of the earphone, which will affect the music effect;
d) Because the earphone makes too close contact with the wall of the ear canal to closely block the ear canal, the user cannot hear the sound from the ambient, which might cause traffic safety problems; and
e) If the earphone is chosen to make loose contact with the wall of the ear canal, the problem of ear fullness due to air tightness can be solved, but the music quality will be greatly compromised due to introduction of the ambient noise.